Baltimore/Washington International Thurgood Marshall in April 2025

78.5%departed on time

BTS: A flight is counted as on time if it arrived less than 15 minutes after its scheduled time. Only carriers with at least 0.5 percent of domestic scheduled passenger revenue report.

In April 2025, reporting carriers scheduled 8,107 domestic departures from Baltimore/Washington International Thurgood Marshall (BWI). 78.5% left less than 15 minutes late and 79.7% reached their destination on time; 0.3% were cancelled.

Nationally that month, 80.6% of flights departed on time and 79.5% arrived on time, so BWI departures were 2.1 points below the national departure figure.

A year earlier, in April 2024, the airport had 8,230 departures with 72.7% leaving on time: a change of +5.8 points, with flights down 1%.

Flights arriving at BWI that month were on time 82.4% of the time (8,113 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 40%, air carrier 35% and national aviation system 23%.

On time 79.7%
Arrived 15+ minutes late 19.8%
Cancelled 0.3%
Diverted 0.2%

Every scheduled departure from BWI in April 2025, judged by arrival at the destination.

April 2025 against a year earlier, the airport's year and the nation

Measure	Apr 2025	Apr 2024	BWI, 12 months to Jul 2026	All reported flights, Apr 2025
Departed on time	78.5%	72.7%	71.7%	80.6%
Arrived on time	79.7%	75.3%	76.4%	79.5%
Cancelled	0.3%	0.6%	1.8%	0.8%
Average departure delay (late minutes only)	12.9 min	15.8 min	16.5 min	14.1 min
Scheduled departures a day	270	274	259	19,465
Scheduled departures	8,107	8,230	94,429	583,950

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
WN Southwest Airlines	6,046	75%	79.9%	3.9 min	0.1%
NK Spirit Airlines	518	6%	82.2%	3.8 min	0.0%
DL Delta Air Lines	424	5%	84.0%	1.9 min	1.2%
UA United Airlines	329	4%	83.9%	6.0 min	0.3%
AA American Airlines	312	4%	74.4%	21.4 min	1.6%
F9 Frontier Airlines	263	3%	68.4%	21.1 min	0.8%
YX Republic Airline	85	1%	84.7%	-1.9 min	0.0%
MQ Envoy Air	66	1%	72.7%	1.7 min	3.0%
AS Alaska Airlines	36	0%	50.0%	14.6 min	2.8%
OH PSA Airlines	28	0%	89.3%	-0.9 min	0.0%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
BWI–MCO	Baltimore to Orlando	470	80.6%	0.9 min	0.4%
BWI–ATL	Baltimore to Atlanta	451	77.4%	7.7 min	1.1%
BWI–BOS	Baltimore to Boston	357	77.9%	3.7 min	0.0%
BWI–FLL	Baltimore to Fort Lauderdale	317	86.1%	0.8 min	0.0%
BWI–TPA	Baltimore to Tampa	281	77.9%	7.3 min	0.4%
BWI–MIA	Baltimore to Miami	266	80.5%	1.6 min	0.0%
BWI–DEN	Baltimore to Denver	230	71.3%	13.0 min	0.0%
BWI–CLT	Baltimore to Charlotte	229	80.8%	15.6 min	0.4%
BWI–ORD	Baltimore to Chicago	209	77.5%	10.9 min	1.9%
BWI–LAS	Baltimore to Las Vegas	187	76.5%	7.9 min	0.0%
BWI–BNA	Baltimore to Nashville	169	87.0%	0.2 min	0.0%
BWI–DTW	Baltimore to Detroit	165	78.8%	6.2 min	1.2%

By scheduled departure hour

On-time share:under 62%6270768288% and over

Share of departures that left less than 15 minutes late, by scheduled hour (local time), April 2025.

Delay causes

BTS cause category	Share of delay minutes	National, Apr 2025	Minutes
Air carrier	35.0%	32.7%	30,843
Late-arriving aircraft	39.7%	39.4%	35,028
National Aviation System	22.8%	22.2%	20,092
Extreme weather	1.5%	5.5%	1,364
Security	1.0%	0.2%	844

88,171 delay minutes on 1,602 flights that arrived 15 or more minutes late and carried a cause report. Carriers assign the categories; see what each category means.

Questions and answers

How many flights left BWI on time in April 2025?

78.5% of 8,107 scheduled domestic departures left less than 15 minutes late, and 79.7% reached their destination on time. The national figures that month were 80.6% and 79.5%.

How does that compare with a year earlier?

In April 2024, 72.7% of 8,230 departures left on time and 0.6% were cancelled, against 78.5% and 0.3% in April 2025.

Provenance

Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance, file for April 2025; public domain. Domestic scheduled flights by reporting carriers, totals and averages only. The site's data runs through July 2026. Full record for BWI · methodology · corrections.